<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>

  <div id="app">
    <child1></child1>
  </div>
  <!-- 引入vue文件 -->
  <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
  <script>
    Vue.component('child1', {
      template: '<h1>组件1</h1>'
    })
    const app = new Vue({
      el: '#app',
      component: {
        child2: {
          template: '<h1>组件2</h1>'
        }
      },
      data: {

      },
      methods: {

      }
    })

  </script>
</body>

</html>